1. Field of the Invention
The present invention relates to an apparatus for handling goods on industrial vehicles, of the type comprising: first guide cog wheels distributed along one end of a vehicle platform; second guide cog wheels distributed along a second end of said vehicle platform and aligned each with one of the first guide cog wheels; a number of roller chains each passing over one of the first guide cog wheels and one of the second guide cog wheels and exhibiting a dragging portion extending longitudinally to the vehicle platform.
In greater detail, the apparatus in reference lends itself to be installed on trucks and/or trailers of tractor semitrailers in order to facilitate the handling of loads on pallets or, at all events, loads consisting of big packages during the goods loading and unloading operations.
2. Prior Art
It is known that, in order to facilitate the handling of goods on industrial vehicles in many cases provision is made for the use of devices essentially consisting of a number of idler rollers having parallel axes which are aligned in several rows extending parallelly along the vehicle loading platform. Under working conditions said rollers slightly project upwardly from the vehicle loading platform so that the goods are enabled to travel thereon without sliding on the platform itself. Once the loading or unloading operations have been completed, the rollers can be lowered so that the goods can directly rest on the vehicle platform and are no longer subjected to displacements while the vehicle is running.
While these devices facilitate the handling of the goods on the vehicle platform, they are not capable of carrying out the handling of the goods in a self-contained manner. In fact, the goods must be always pushed by hand or by other systems in order to achieve their handling.
In view of eliminating this drawback other devices have been provided which comprise a number of flexible cables extending each between respective guide pulleys operable in rotation by one or more motors. Each cable has a dragging portion arranged so as to slide, as a result of the operation of the respective pulleys, along an antifriction guide extending longitudinally on the vehicle platform. The goods disposed on the loading platform lay on the dragging portions of the cables and can therefore be displaced when said cables are moved.
These devices offer an improved operation as compared with those using idler rollers but, on the other hand, they have some drawbacks too.
One drawback resides in that, in spite of the fact that the cables rest on guides made of antifriction material, the handling of the goods always needs an important waste of energy, so as to win frictions developing between the cables and said guides. In addition, antifriction guides are subjected to wear and must be periodically replaced.
Another drawback is given by the fact that the goods laying on the cables are slightly raised with respect to the vehicle platform also when the vehicle is running. Taking into account this precarious support it is clear that during the running undesired shiftings of the goods on the platform can easily take place.
Other envisaged devices use roller chains instead of the above flexible cables. In known solutions these devices are conceptually identical to the previously described devices and therefore they exhibit the same drawbacks as with the use of cables.
Another drawback of the devices of the known art is that they can be installed only on motor vehicles in which the vehicle platform and frame have been previously arranged for the engagement of the different members forming the device itself. Therefore these devices can only be mounted on loading platforms constructed expressly and offering appropriate expedients. If on the contrary the device needs to be installed on a vehicle platform devoid of said expedients, long working times are necessary in view of adapting the platform to installation requirements of the device.